The business case is the document that provides the justification and rationale for initiating a project or program. It describes the business need, the expected benefits, the strategic alignment, the feasibility, and the financial analysis of the proposed solution. The business case is the primary source of information for creating business value and should be reviewed and updated throughout the project life cycle. The project manager should meet with the sponsor, who is the person or group that provides resources and support for the project and is accountable for enabling success, to review the business case and understand the opportunities to create business value. The other options are not the first actions that the project manager should take, as they do not directly address the customer's question or the project's alignment with the business objectives. References:
* [PMBOK Guide], 6th edition, pages 29-31, 33-34, 75-76.
* [Professional in Business Analysis (PMI-PBA) Handbook], pages 9-10, 13-14.